SW
2004-Jan-07 19:40 UTC
2.4 Kernel and Hyperthreading (was Re: [Asterisk-Users] P4 processor
>but if I disable hyperthreading (noht on the kernel line in lilo/grub)Could the same result could be obtained if hyperthreading is disabled from the BIOS ? Supermicro Motherboards (most Phoneix based) have this option Also, would we see same pops and clicks in a dual CPU box (Zeon) then ? SW Message: 1 Date: Wed, 07 Jan 2004 14:32:16 -0500 From: Jeremy McNamara <jj@nufone.net> To: asterisk-users@lists.digium.com Subject: 2.4 Kernel and Hyperthreading (was Re: [Asterisk-Users] P4 processor with Hyperthreading and Asterisk) Reply-To: asterisk-users@lists.digium.com mattf wrote:>Is Asterisk's high memory usage canceling out most of the performancegained>by using HT? > > >In my experience, I've found that hyperthreading is a major problem on Linux Kernel 2.4. If I turn on hyperthreading and start to load up an Asterisk box we get ratty sounding audio along with pops, clicks and ticks, but if I disable hyperthreading (noht on the kernel line in lilo/grub) and all of those anomalies go away and the box scales a whole lot higher. The problem is that the 2.4 Kernel sees the one hyperthreaded processor as two totally separate processors, so the 2.4 kernel tends to mess up, badly, when scheduling the processing. This problem was delt with in the 2.5 kernel and i've been told by quite a few trusted people that it works flawlessly, but i'm not about to run a unstable kernel (or even anything less than like 2.6.14) on any of my production boxes. Jeremy McNamara